Brassinosteroids (BRs) play pivotal roles in the regulation of many dimensions of a plant’s life. Hence, through extensive efforts from many research groups, BR signaling has emerged as one of the best-characterized plant signaling pathways. The key molecular players of BR signaling from the cell surface to the nucleus important for the regulation of plant growth and development are well-established. Recent data show that BRs also modulate plant responses to environmental stresses such as drought and pathogen infection. In this mini review, we present the recent progress in BR signaling specifically in the post-translational SUMO modification of BR’s master regulators, BES1/BZR1. We also discuss recent findings on the crosstalk between BR, UV light, and jasmonic acid signaling pathways to balance growth during light stress and pathogen infections. Finally, we describe the current update on the molecular link between BR signaling and intracellular auxin transport that essential for plant development.

SummaryIn response to high CO2 environmental variability, green algae, such as Chlamydomonas reinhardtii, have evolved multiple physiological states dictated by external CO2 concentration. Genetic and physiological studies demonstrated that at least three CO2 physiological states, a high CO2 (0.5–5% CO2), a low CO2 (0.03–0.4% CO2) and a very low CO2 (< 0.02% CO2) state, exist in Chlamydomonas. To acclimate in the low and very low CO2 states, Chlamydomonas induces a sophisticated strategy known as a CO2‐concentrating mechanism (CCM) that enables proliferation and survival in these unfavorable CO2 environments. Active uptake of Ci from the environment is a fundamental aspect in the Chlamydomonas CCM, and consists of CO2 and HCO3– uptake systems that play distinct roles in low and very low CO2 acclimation states. LCI1, a putative plasma membrane Ci transporter, has been linked through conditional overexpression to active Ci uptake. However, both the role of LCI1 in various CO2 acclimation states and the species of Ci, HCO3– or CO2, that LCI1 transports remain obscure. Here we report the impact of an LCI1 loss‐of‐function mutant on growth and photosynthesis in different genetic backgrounds at multiple pH values. These studies show that LCI1 appears to be associated with active CO2 uptake in low CO2, especially above air‐level CO2, and that any LCI1 role in very low CO2 is minimal.

Microalgae and cyanobacteria contribute roughly half of the global photosynthetic carbon assimilation. Faced with limited access to CO2 in aquatic environments, which can vary daily or hourly, these microorganisms have evolved use of an efficient CO2 concentrating mechanism (CCM) to accumulate high internal concentrations of inorganic carbon (Ci) to maintain photosynthetic performance. For eukaryotic algae, a combination of molecular, genetic and physiological studies using the model organism Chlamydomonas reinhardtii, have revealed the function and molecular characteristics of many CCM components, including active Ci uptake systems. Fundamental to eukaryotic Ci uptake systems are Ci transporters/channels located in membranes of various cell compartments, which together facilitate the movement of Ci from the environment into the chloroplast, where primary CO2 assimilation occurs. Two putative plasma membrane Ci transporters, HLA3 and LCI1, are reportedly involved in active Ci uptake. Based on previous studies, HLA3 clearly plays a meaningful role in HCO3− transport, but the function of LCI1 has not yet been thoroughly investigated so remains somewhat obscure. Here we report a crystal structure of the full‐length LCI1 membrane protein to reveal LCI1 structural characteristics, as well as in vivo physiological studies in an LCI1 loss‐of‐function mutant to reveal the Ci species preference for LCI1. Together, these new studies demonstrate LCI1 plays an important role in active CO2 uptake and that LCI1 likely functions as a plasma membrane CO2 channel, possibly a gated channel.

Dengan semakin meningkatnya kasus terkonfirmasi positif COVID-19 di wilayah provinsi Nusa Tenggara Timur (NTT), suatu metode pemeriksaan diagnostik yang dapat menganalisa sampel dalam jumlah banyak dengan waktu singkat menjadi sangat imperatif untuk dilakukan. Menyikapi hal ini, sejumlah putra-putri NTT yang tergabung dalam organisasi Forum Academia NTT (FAN) memprakarsai penerapan metode pooled-test untuk analisa diagnostik sampel COVID-19 yang diharapkan dapat mengoptimalkan program pemerintah dalam mempercepat penanganan penyakit ini di wilayah NTT. Pada Maret 2020 lalu, sebanyak 13 teknisi laboratorium (laboran) telah berhasil diseleksi yang akan ditempatkan pada Laboratorium Biomolekuler Kesehatan Masyarakat Provinsi NTT, khususnya untuk menjalankan prosedur analisis sampel menggunakan metode tersebut di atas. Akan tetapi, sebelum para laboran ini siap beraktivitas, diperlukan suatu pelatihan khusus yang dapat membekali mereka dengan kompetensi dan keterampilan dasar yang diperlukan. Pada Juni 2020, pelatihan Biomolekuler tahap I telah dilaksanakan yang memiliki maksud dan tujuan tersebut. Topik pelatihan yang diajarkan berupa: Pengenalan Biosafety Lab dan Biosafety Cabinet, Teknik Penggunaan Mikropipet, Teknik Analisis DNA/RNA menggunakan metode Elektroforesis, Nano-Spektrofotometer, PCR dan qPCR, serta Pengenalan metode Pooled-test. Berdasarkan hasil observasi, para peserta dianggap telah cukup menguasai berbagai teknik Biomolekuler Dasar yang diajarkan yang diharapkan dapat berkontribusi terhadap hasil penanganan analisis sampel yang lebih akurat, terpercaya dan dapat dipertanggungjawabkan.

Dengan semakin meningkatnya kasus terkonfirmasi positif COVID-19 di wilayah provinsi Nusa Tenggara Timur (NTT), suatu metode pemeriksaan diagnostik yang dapat menganalisa sampel dalam jumlah banyak dengan waktu singkat menjadi sangat imperatif untuk dilakukan. Menyikapi hal ini, sejumlah putra-putri NTT yang tergabung dalam organisasi Forum Academia NTT (FAN) memprakarsai penerapan metode pooled-test untuk analisa diagnostik sampel COVID-19 yang diharapkan dapat mengoptimalkan program pemerintah dalam mempercepat penanganan penyakit ini di wilayah NTT. Pada Maret 2020 lalu, sebanyak 13 teknisi laboratorium (laboran) telah berhasil diseleksi yang akan ditempatkan pada Laboratorium Biomolekuler Kesehatan Masyarakat Provinsi NTT, khususnya untuk menjalankan prosedur analisis sampel menggunakan metode tersebut di atas. Akan tetapi, sebelum para laboran ini siap beraktivitas, diperlukan suatu pelatihan khusus yang dapat membekali mereka dengan kompetensi dan keterampilan dasar yang diperlukan. Pada Juni 2020, pelatihan Biomolekuler tahap I telah dilaksanakan yang memiliki maksud dan tujuan tersebut. Topik pelatihan yang diajarkan berupa: Pengenalan Biosafety Lab dan Biosafety Cabinet, Teknik Penggunaan Mikropipet, Teknik Analisis DNA/RNA menggunakan metode Elektroforesis, Nano-Spektrofotometer, PCR dan qPCR, serta Pengenalan metode Pooled-test. Berdasarkan hasil observasi, para peserta dianggap telah cukup menguasai berbagai teknik Biomolekuler Dasar yang diajarkan yang diharapkan dapat berkontribusi terhadap hasil penanganan analisis sampel yang lebih akurat, terpercaya dan dapat dipertanggungjawabkan.